21/11/2013 10:01

"It appears that one of the most problematic things about keeping Brit Bikes running properly is the carburetors. The old Amals are prone to warpage and wear, not to mention fuel leakage, etc. Well, help is on the way! No, not from Mikuni or some other make, which will introduce problems of their own.

This hope is the new Amal Premier from the Burlen Company, which took over building Amal carburetors. I was fortunate to get a couple of these "premiers" from John Healy of Coventry Spares to give them a real world trial.

When they arrived, the first thing I noticed was they appear to be significantly better in quality; both in material and casting. Dismantling them you find a new type float, not the old yellow hollow plastic, but a solid material with a metal bendable tab for level adjustment I set it up about .040 thousandths below the lip of the bowls.

The slides are more substantial anodized aluminum and are reminiscent of the slides in the MK III carbs. The needle and .106 needle jets are the same as we are used to seeing with the two rings on the top of the needle. The idle jets seemed a bit smaller, as my #78 drill wouldn't enter without pressure, which I didn't care to do.

Looking them all over and setting them up the same as my old Amals except #3 slides instead of the #3 1/2, I was ready to mount them on my '70 Bonnie which has 67K miles on it

The bike I chose to try these new "premiers" on has a homebuilt 76-degree crank, #54 Kenny Harmon cams and Boyer ignition. The crank is 1 1/2 pounds lighter than the '66-'67 light cranks, and the result of the light flywheel effect is that if the carburation at idle is not perfect it will quit. Normally, I had to idle at 1100-1200 rpm to be reliable with the old carbs.

On the road, the first thing I noticed was that the slight hesitation on downshift was gone, possibly because of the change to #3 slide from the original #3 & a 1/2, I understand that the new carbs have a completely different idle system and it really works.

Now I am able to get a reliable idle at 900-100 rpm vs the 1100-1200 rpm before. Most of my everyday riding (70- 1OO-plus miles) is on the open roads at 60-65 mph, with very little city riding. I keep an individual notebook on each bike to record gas mileage, oil changes, and any repairs necessary,

A surprise awaited at the gas pump! As I was used to mileage in the high forty to low fifties, the new "premiers" are getting high sixties to into the low seventies in US gallons!

To summarize, after riding a couple of thousand miles on these new Amals I am a believer! If you have the new "premier" carb or carbs on your Brit Bike and it doesn't run right, chances are it isn't carburetion!"